There are two predominant types of systems used by home telephone or small office locations to answer telephone calls and electronically store telephone messages. The first is the common answering machine; the second is to subscribe to voice mail service provided by a central provider, such as the local telephone company. Each of these system have advantages and disadvantages compared with the other system. Central messaging systems are more reliable than home answering machines. The central systems use digital storage methods and often use redundant systems so that if a hard disk or other hardware system malfunctions, the system still operates correctly, without loss of data. If the subscriber""s home loses power, the central messaging system keeps working while the home answering machine stops working. Central messaging systems can also handle more than one incoming call at a time for the same home telephone number. Home answering machines, on the other hand, only handle one call at a time and if a second call comes in, the second call gets a busy signal if the home does not have call waiting. If the home has call waiting, a possibly worse result may occur; the caller hears endless ringing, as the home answering machine is not able to answer call waiting calls, and the caller may assume that the phone number does not have answering machine and thus may not call back shortly to leave a message, with the result that the home user may miss an important message. Last, central messaging systems are often much easier to access by the subscriber when the subscriber is away from home. While many home answering machines have remote message retrieval features, the user interfaces are often clumsy and ineffective. Central messaging systems also sometimes have toll free numbers for out of town subscribers to use to retrieve messages.
Home answering machines, on the other hand, have certain advantages over existing central messaging systems. One advantage of home answering machines is that when the subscriber walks into the home and there are messages waiting, a red light, illuminated number or other visual indication is given on the home answering machine to indicate that the machine has received new messages. On most central messaging systems, the subscriber must actively take some action, such as pick up a telephone receiver to see if there is stutter dial tone instead of the normal dial tone, in order to find out if there are new messages waiting. The other main advantage of home answering machines is that they can be used to screen incoming telephone calls. Many home answering machine users do not answer telephone calls even when they are home. Rather, they let the answering machine answer the telephone call, play the greeting message, let the caller begin to leave a message and identify the caller before they decide whether to answer the telephone call or not. With a central messaging system, once an unanswered call is answered by the messaging system, the subscriber cannot listen to the message being left or decide to answer the call.
It is desired to have a system that has the advantages of each of these systems with few or none of the disadvantages.